Heat exchangers may be employed to exchange heat between two or more fluids. One example embodiment of a heat exchanger is a plate heat exchanger. Plate heat exchangers may employ a plurality of plates to transfer heat between first and second fluids. In this regard, the plates may be sandwiched together to form plate assemblies that may include apertures or groves therein that define flow channels through which one of the fluids may flow. The plates may be assembled in a manner such that the plate assemblies alternate the fluid carried therein and thereby the first fluid may travel through a plate assembly that may be beside (or sandwiched between) one or more plate assemblies through which the second fluid travels. Accordingly, the plates that separate the fluids may function to transfer heat between the two fluids. The plates may be configured to define relatively large surface areas such that fluid transfer between the fluids is improved.
One example embodiment of a plate assembly is illustrated in FIGS. 1A-C. This plate assembly may be included in heat exchangers manufactured by CHART INDUSTRIES of Garfield Heights, Ohio. The plate assembly 100 may include first 102 and second 104 flow plates that are sandwiched between spacer plates 106, 108. The spacer plates 106, 108 separate the plate assembly 100 from adjacent plate assemblies as discussed above. The flow plates 102, 104 may function to create flow channels through which a fluid may flow. As illustrated in FIG. 1C, the plates may be configured to create a turbulent flow path 110 through each of the flow channels, which may assist in heat transfer by slowing the flow of the fluid therethrough. The flow channels may be defined by a plurality of orifices 102A, 104A which are offset from one another and cause the flow path 110 to be serpentine.
A second example embodiment of a plate assembly is illustrated in FIGS. 2A and 2B. This plate assembly may be included in heat exchangers manufactured by HEATRIC, of Houston, Tex. As illustrated, the plate assembly 200 includes a flow plate 202 and a spacer plate 206. The flow plate 202 includes grooves 202A defined therein, which each define flow channels through which fluid flows along a turbulent flow path 210, as illustrated in FIG. 2B. Since the grooves 202A do not extend all the way through the flow plate 202, the flow plate functions as a second spacer plate with the grooves defining flow channels between the flow plate and the spacer plate 206.
Accordingly, prior art embodiments of heat exchangers may be designed to provide transfer of heat between fluids by causing turbulent flow paths for fluids between plates defining relatively large surface areas. As seen by the foregoing, however, known plate heat exchangers typically include multiple flow paths that define individual runs along the heat exchanger from the inlet to the outlet such that the individual runs have no fluid connection one with another between the inlet and the outlet. In this configuration, a blockage of an individual run prevents the blocked run from participating in heat exchange along its entire length and thus reduces heat exchange capacity of the overall device by the fraction of the area encompassed by the run. Since known heat exchangers can suffer from this and other limitations that may be addressed by the present disclosure, there remains a need in the art for improved heat exchangers.